Summary

• Turkey and Russia are the dominant powers in the Black Sea. They maintain a delicate balance of competition and cooperation as each seeks to contain the other but also to avoid triggering a war.
• Turkey’s cautious approach towards Russia has led it to prioritise regional stability over alignment with EU and NATO policies, straining relations with the West.
• As Europe faces shifting US policies and the challenge of containing a post-war Russia, renewed cooperation with Turkey is essential. The Black Sea could be the first step.
• NATO should prioritise mini-partnerships with Ankara in the Black Sea, using Turkey’s preference for regional cooperation with Romania and Bulgaria over high-profile engagements with non-coastal allies.
• The EU should foster collaboration in areas of mutual interest—such as Black Sea security, Caucasus stability and defence-industrial cooperation—to improve its relations with Turkey.
• A pragmatic reset in Turkey-EU relations could enhance each side’s ability to contain Russia, a shared goal, and include Turkey in the post-Ukraine war European security architecture.

“It’s complicated”

“Our Black Sea” was how Turkish president Recep Tayyip Erdogan described it when he visited his Russian counterpart, Vladimir Putin, in September 2023. The meeting would revive a deal that allowed embattled Ukraine to export grain and other commodities from its Black Sea ports.

The comment could have been an acknowledgment of a political reality: Turkey and Russia are the dominant players in the Black Sea. The sea is also central to Putin’s great power ambitions. Russia has historically used it as a launchpad for its imperial power projections and to protect its southern flank before its armies can move towards eastern Europe or the Caucasus. It is also Russia’s shortest route to the warm waters of the Mediterranean and the Suez Canal. But Turkey has the longest coast in the Black Sea and controls access to the Mediterranean via the Turkish straits: the Bosphorus and the Dardanelles. The 1936 Montreux Convention granted Turkey the authority to regulate naval access to the Black Sea via the straits—putting to rest a recurrent point of contention that helped cause nearly a dozen wars with Russia in the preceding couple of centuries.

The Black Sea is the southern front of the Ukraine war and Ukraine’s only outlet to the high seas—a lifeline for its economic and military survival as an independent and sovereign nation. After Russia’s invasion of Ukraine, Ankara invoked the Montreux Convention to close the straits to the warships of “belligerent powers”. Despite an exception that allows Black-Sea-based warships to return to their home ports after the closure (including Russia’s and Ukraine’s), Turkey went further, closing the Turkish straits to military vessels of all countries—Russian, Ukrainian or NATO. This left Russia unable to reinforce its Black Sea Fleet, which became vulnerable to Ukrainian attacks. But it also meant NATO warships from non-coastal states could not enter the Black Sea to help Ukraine. This demonstrates the balancing act Turkey has maintained: supporting Ukraine without triggering a NATO-Russia escalation off its shores.

In fact, since the end of the cold war, Turkey has been careful to avoid grandstanding in the Black Sea that could provoke Russia. But, at the same time, it has been wary of Russian ambitions to dominate the region and has used a containment strategy where it could. Russia, for its part, aims to: prevent Turkey from stifling it in the Black Sea; drive a wedge as far as possible between Ankara and its Western partners; and stop it from gaining more power in the region. This delicate balancing act forms the basis of their kabuki dance of competition and cooperation—or “co-opetition”.

Their unusual relationship has raised eyebrows in the West. Turkey faced criticism in Europe for bucking European sanctions against Russia after the latter annexed Crimea in 2014, and then again after Russia’s full-scale invasion of Ukraine. Not only that, but over the past decade Turkey has also developed close economic relations with Russia.

Turkey’s closer relations with Russia coincided with its drift from the West. For much of the past decade, EU officials saw Turkey as a significant strategic challenge and focused more on containing its assertive policies than on figuring out a way to engage with this regional heavyweight. Europeans had a long list of complaints when it came to Turkish policy in Syria and Libya, as well as in the eastern Mediterranean, where Turkey has flexed its muscle in maritime disputes with Greece and Cyprus in what European critics have called gunboat diplomacy.

There was no love lost on the Turkish side, either. European weapons embargoes against Turkey in reaction to its operations in Syria from February 2015 onwards irritated Turkish policymakers. Turkish politicians also deplored the weak European response to the 2016 coup attempt in Turkey and its aftermath. They generally believed that some EU member states were actively undermining Turkey’s ascendance and regional influence. This created, at the very least, suspicion toward European intentions in Turkey. The Turkish public generally agreed but kept supporting an EU future for Turkey.

But three years of war in Ukraine have created a new reality for both Europe and Turkey. The conflict has highlighted the existential threat from a revisionist Russia and the breakdown of the rules-based order. The Trump administration’s rush to strike a deal with the Kremlin, even in the absence of security guarantees for Ukraine, also raises questions about the future of transatlantic unity and European security. While unwilling to provoke Moscow, Ankara is now also worried about the return of a revanchist foe. A Russia that perceives itself as victorious would reinforce Moscow’s expansionist ambitions, increasing the risk of aggression against Moldova, the Caucasus, the Baltic states, or Poland. It would also cast doubt on the European ability to deter Russian aggression.

European NATO allies and Turkey would benefit from deepening their cooperation to contain Russia in the Black Sea and to secure Ukraine’s future. This paper sets out how they should do this. It also outlines how Black Sea cooperation via NATO could become a bridge for the EU to repair its ties with Turkey, with a view to a wider European-Turkish defence partnership in the future.  

Shifting power in the Black Sea

“An astounding ten wars have taken place on or near the Black Sea littoral since the end of the Cold War, more than any other maritime space in the world.” Maximilian Hess.

The balance of military power in the Black Sea has historically fluctuated between Russia and Turkey. Turkey emerged as the dominant force in the immediate aftermath of the breakup of the Soviet Union.

The post-cold war period also saw shifting political alignments among the six countries that border the Black Sea. Bulgaria and Romania became NATO allies in 2004 and EU members in 2007, while Turkey is an EU membership candidate and NATO ally. In the early 2000s, Georgia, Moldova and Ukraine all sought closer alignment with the West, with all three countries declaring an interest in joining the alliance.

This prompted Russia to respond to the growing influence of NATO and the West in the Black Sea with challenges to these states’ sovereignty. It invaded Georgia in 2008 and annexed Crimea in 2014. The annexation of Crimea led to the militarisation of the Black Sea, with Russian attempts to create “no-go” zones against NATO allies by using air and land-based missile systems. That militarisation allowed Russia to dominate the Black Sea until 2023, when Ukrainian attacks incapacitated almost half of its Black Sea fleet, including its flagship cruiser, “Moskva”. As a result, the naval balance of power in the Black Sea shifted again from Russia to Turkey.

Turkey’s navy today is the strongest in the Black Sea, boasting advanced frigates, submarines and an amphibious assault ship. This came as much from the Turkish government’s modernisation programme over the last three decades as the weakening of the Russian Black Sea fleet. In line with its pursuit of regional power and an autonomous foreign policy, Ankara envisioned a robust maritime presence to defend its interests in surrounding seas, including the Black Sea and the Mediterranean. Dubbed the “Blue Homeland” doctrine, it aimed to enhance Turkey’s presence in its sea areas and project power where it has a military presence, such as Somalia and Libya. The commissioning of a light aircraft carrier, the TCG Anadolu, in 2023 symbolised Ankara’s commitment to enhancing its naval power projection capabilities.

But Turkey’s Black Sea strategy is also fundamental to its relationship with Ukraine. The Turkish government has been helping Ukraine defend itself by selling it drones and other defence equipment, and jointly producing drones. It has also increased its cooperation with NATO on various mechanisms to support regional stability. For example, Turkey maintains round-the-clock air and naval reconnaissance missions in the Black Sea and provides up to 67% of all situational awareness information to NATO and Ukraine. It also stopped the Russian navy from passing through the Turkish straits, which allowed Ukraine to decimate Moscow’s Black Sea Fleet.

Turkey and Russia are neither allies nor form an axis. Europe’s interests in the Black Sea thus overlap with Turkey’s: containing Russia and ensuring the survival of Ukraine, but also maintaining the independence of coastal EU member states like Romania and Bulgaria, which Russia aims to manoeuvre away from the West. But the Turkey-Russia relationship is far from straightforward.

Between Russia and the West

Despite their power struggles in various regions, Ankara and Moscow have effectively compartmentalised their relations in a way rarely seen in interactions between states. For example, although they support opposite sides in Libya, Syria and the Caucasus, Turkey and Russia have deepened their economic ties and sought mutually acceptable solutions through initiatives like the Astana process in Syria and the Berlin conference for a ceasefire in Libya.

Apart from a short but destructive period of tensions in 2015 after Turkey downed a Russian jet near its border with Syria, the two governments have established a modus vivendi. At the political level, they share a disdain for the Western-led order and recognise each other’s concerns and interests in their neighbourhood. At a working level, they have found a rhythm to cooperate begrudgingly.

Turkey has also been keen to fend off nearby conflicts from spilling onto the Black Sea and ensure freedom of navigation across it. At times, this has meant that the government has refrained from directly challenging or provoking Russia, even by preventing Western navies from entering the Black Sea by invoking the Montreux Convention.

However, Turkey and Russia are aligned on few issues and do not have an institutional security framework for cooperation like NATO. Their political and economic deals have been negotiated at the leadership level. The government in Ankara views Russian expansionism as a dangerous threat to its regional interests. In Syria, the Caucasus, Africa and Libya, the two compete for power and influence.

Turkey’s caution in its dealings with Russia is undoubtedly a legacy of the Ottoman-Russian wars but also a reflection of its desire to avoid confrontation with a revisionist neighbour to the north. Since the Russian annexation of Crimea in 2014, Turkey has prioritised preserving its delicate balance of power with Russia over the demands of its Western partners. For example, when facing demands for greater NATO access and for cooperation from European or other coastal states, like Romania or Bulgaria, Turkish officials point out that NATO is “already” in the Black Sea. One Turkish official noted at a gathering of US and European officials, “We are already there. Aren’t we a NATO country?”[1]

This has all contributed to Turkey’s relative estrangement from the West, and especially the EU, over the past decade.

The drift from the West

Besides the issue of Russia, Europe’s leaders saw Turkey’s assertive security and foreign policy in Syria, Libya and the eastern Mediterranean as a challenge to European interests. They also witnessed Turkey’s democratic and human rights gains backslide, which are key priorities for the EU since Turkey was still, technically speaking, a candidate for membership. This all helped strip relations between Western leaders and the Turkish president down to a bare minimum. Turkey’s EU accession process was suspended for all practical purposes.

Meanwhile, Turkey’s ties with the US and other key NATO partners have been lukewarm since 2015. This is due to diverging threat perceptions, differing regional policies and mutual grievances. Turkey, for example, blamed America, its main Western ally, for a coup attempt against the Turkish government in 2016. Indeed, a large cross-section of Turkish society saw this as a US-backed plot. Turkish leaders also felt betrayed by American cooperation with the Syrian Democratic Forces because of the group’s affiliation with the Kurdistan Workers’ Party, which has been waging an armed struggle against Turkey since the 1980s and is designated a terrorist group by Turkey, the EU and the US.

This divergence on Syrian Kurds further created the mood music for closer cooperation with Russia in Syria. In 2019, after several years of turmoil in Turkey-US ties, Turkey purchased an S-400 missile system from Russia, triggering US sanctions on Turkey’s defence industry. During 2015-2019, Turkey intervened three times in northern Syria to curb US-backed Kurdish groups.

Turkey had also been positioning its powerful navy in the eastern Mediterranean to support its maritime claims. The increase in Turkey’s naval capacity alarmed some NATO allies, particularly Greece, which has longstanding maritime border disputes with Turkey in the Aegean Sea and now in the eastern Mediterranean. Since 2015, successive US administrations have viewed these actions with suspicion and as a departure from Turkey’s pro-Western course and its traditional role as a loyal and close US ally, slapping Turkey with sanctions and criticism. US politicians have described Turkey as an “unfaithful ally” due to its policies.

Russia has benefited from Turkey’s divergence from the West. It has filled the European void to deepen economic cooperation, finalise the construction of the TurkStream pipeline across the Black Sea and win the bid to build Turkey’s first nuclear reactor—widening Turkey’s energy dependency on Russia. But Turkey’s Black Sea strategy also means it has been one of Ukraine’s staunchest defenders since 2022.

Defending the Black Sea (and Ukraine) since 2022

Following the all-out invasion, Turkish relations with the West improved, but only marginally. Notably, Turkey’s decision to continue trading with Russia despite the invasion caused some consternation among European governments. But Turkey had been a key defence ally for Ukraine even before the war and a natural partner in containing Russia. Ankara and Kyiv were in discussions on deepening their defence partnership before the invasion; Erdogan has long supported NATO membership for Ukraine and Turkey has been active in defending Ukraine and the rest of the Black Sea since the start of the war.

Working with NATO

Turkey has cooperated with NATO since February 2022 in various domains, even though it has eschewed high-profile engagements to avoid provoking Russia. For example, in June that year Ankara assumed the command of the maritime component of NATO’s Very High Readiness Joint Task Force. Its Rapid Deployable Corps, based in Istanbul, then became a designated NATO Warfighting Corps in December 2022 for contingencies in 2023. This meant Turkey effectively spearheaded NATO’s response to possible further Russian aggression against allies.

Moreover, in January 2024, Turkey signed an agreement with Romania and Bulgaria to establish a Mine Countermeasures Black Sea (MCM Black Sea) Task Group among the three NATO allies to jointly tackle drifting sea mines that have threatened Black Sea shipping since the start of the war. Turkey also supports NATO’s forward presence in Romania and Bulgaria. It became a contributing nation to the NATO battlegroup in Bulgaria and sent four F16 aircraft and 80 personnel to augment the national air policing capabilities of Romania from December 2023 to March 2024. The Turkish government has also pledged to contribute to NATO’s Baltic Air Policing Mission in Estonia in 2026. These moves represent Turkey’s preferred “regional solutions for regional problems” approach.

Arming Ukraine

Despite pessimistic views in the West of Kyiv’s ability to liberate all its territory, the government in Ankara wants Ukraine to survive and ensure it keeps a significant shoreline in the Black Sea. This means its support has gone beyond its NATO leadership in the Black Sea.

Turkey is committed to upgrading Ukraine’s military capabilities. In the early days of the war, the delivery of Turkish Bayraktar TB2 drones strengthened Ukrainian defences against Russian attempts to seize Kyiv.

In fact, Turkey had signed a military cooperation agreement with Ukraine days before Russia invaded. Turkish deliveries of additional TB2s with air-to-ground missiles shored up Ukraine’s defence before Western military aid arrived. Indeed, these missiles put Turkey ahead of other NATO members in providing Ukraine with lethal military equipment.

Turkish companies continue to quietly supply weapons and much-demanded ammunition to Ukraine. Turkey is also helping Ukraine upgrade its maritime capabilities by building corvettes under MILGEM, Turkey’s national warship-building programme.

And yet, the Turkish government has long argued that the war in Ukraine should end sooner rather than later—through negotiations—and it has been keen to play a role in this. The first round of serious negotiations between Russia and Ukraine in March 2022 took place in Istanbul. Two months later, Turkey brokered the “grain deal” in cooperation with the UN, which provided a mechanism in Istanbul for monitoring and vetting civilian maritime trade. In April 2024, Turkey facilitated a prisoner exchange between Russia and Ukraine.

Turkey tried again to build on the successes of its earlier diplomacy in the summer of 2024 when it hosted talks between Ukraine and Russia on Black Sea freedom of navigation. Turkey hoped to stretch this into a temporary moratorium on hostilities on ports and energy infrastructure, Turkish and former US officials revealed to the authors following the dialogue.[2] However, the talks came to an end in August 2024 with Ukraine’s offensive in Kursk region.

The West in search of a Black Sea strategy

Unlike Turkey, until the war started, the EU, the US and NATO lacked a unified strategy to address political and security challenges in the Black Sea. However, the full-scale invasion forced US and European officials to consider a strategy for the region. The past three years have underlined to Western powers how vital the Black Sea is to their strategic interests.

The Black Sea Security Act was introduced in both houses of the US Congress in March 2023 to end this strategic blindness. Still, it was dominated by Ukraine-related security issues and did not overhaul American strategy as expected. Similarly, the EU Commission’s Black Sea Synergy does not go beyond a hotch-potch of environmental and social policies with a nod to supporting Ukraine.

In its 2022 Strategic Concept, NATO finally declared the Black Sea region of strategic importance, ending years of neglect, but failed to go further. This recognition has not yet become a comprehensive strategy that encompasses political and economic developments or includes a renewed partnership with Turkey.

But with the Black Sea as the new centre of gravity for European security, a longer-term strategic foresight is needed for Europeans to deal with the fragmentation of power, containment of a post-war Russia, shifts in military balance and the multiple crisis zones in the region. NATO and the EU have yet to identify a coordinated Black Sea strategy that is achievable, sustainable and able to curb Russian overreach while protecting the freedom of choice for coastal states.

Another reason for Europe to re-energise relations with Turkey is the uncertainty surrounding European security in light of shifting US policies. The Trump administration has signalled that Europeans must assume more responsibility for their defence. Yet, even beyond that, US leaders seem willing to weaponise Europe’s dependency on America for its defence and energy needs. President Donald Trump already paused—then restarted, then paused, then restarted—US arms shipments to Ukraine and froze all USAID deliveries. He has also indicated that he is considering punitive tariffs on Europe.

European-Turkish defence cooperation

Core EU member states have been sceptical about inviting Turkey into a discussion on the end of the war in Ukraine, EU defence programmes and broader European security. But Trump’s return is helping European leaders come to terms with their shared interests with Turkey. In early March 2025, for example, Turkish leaders were invited to a pan-European summit in London to discuss plans for a potential European tripwire force inside Ukraine to deter further Russian aggression in the event of a ceasefire. Turkey has also been invited to attend the EU leaders’ summit to be held in Brussels on March 20th-21st this year.

Over the past three years of war, many European citizens’ perceptions of Turkey have also softened.

Meanwhile, Trump’s desire to slap the EU with punitive tariffs while he pursues a reset with Putin has made clear that continued US support for Europe’s defence is becoming politically unviable. The Trump administration would like Europe to do more for its own defence. The increasingly tense transatlantic relationship could deter US companies from participating in European defence production.

Turkey could help fill this gap, but Europeans will have to overcome bilateral issues that blocked greater cooperation in the past. France presented one sticking point in this regard. Over the past decade, French-Turkish relations have been tepid because of human rights concerns raised by Paris and a sense of strategic rivalry that grew stronger between the two countries. After the war in Ukraine started, French leaders argued that the EU should only supply weapons to Ukraine procured from European defence firms to support European industry and maintain the EU’s strategic autonomy. However, given that the European defence industry lacks the capacity to meet demand, France eventually dropped its objections under pressure from Ukraine and other EU member states.

Greece had also argued that EU money should not be used to fund Turkish defence companies, which, in the end, would strengthen the Turkish military’s ability to challenge European interests in its neighbourhood. However, once France ended its opposition, Greece also softened its stance.

The removal of French objections to non-EU states and companies tapping the European Defence Fund could lead to further entrenchment by agile Turkish defence companies in European defence production. The manufacturer of the successful TB2 drones, Baykar, co-owned by Erdogan’s son-in-law, acquired the Italian company Piaggio Aerospace in December 2024 with the aim of better positioning itself in Europe. With regard to Black Sea security, the EU could help finance Turkey’s defence industry to build ships for Romania and Bulgaria (in addition to Ukraine). This would strengthen EU and NATO maritime presence in the region and boost the sales of Turkish defence manufacturing products to countries on the eastern flank.

Several European countries already procure Turkish defence products or cooperate with Turkish companies in their production, including drones, armoured vehicles and ammunition. Turkish drones have proven effective in conflicts in Libya, Syria, Ukraine and the Caucasus against Russian-built defence systems. They are cheaper than their equivalents and come with fewer—or no—restrictions.

While these issues go far beyond Black Sea security, a credible partnership on the defence of the Black Sea could later be developed in integrating Turkey into broader European defence initiatives, such as Permanent Structured Cooperation on defence.

This is precisely the kind of cooperation that NATO and the EU should pursue with Turkey in the face of a fragmenting global order.

How Turkey, NATO and the EU can work together

The core principles of the transatlantic alliance are under threat. This presents a unique opportunity to re-establish ties between Turkey and Europe around a pragmatic and mutually beneficial collective security partnership.

Turkey’s relationship with NATO is the central element of its national security identity but is not its sole pillar. Even if Turkey seeks better relations with the West, it will also continue to pursue an autonomous foreign and security policy in its neighbourhood.

Turkey and NATO

A sustainable framework for the Black Sea will have to balance NATO’s strategic priorities with Turkey’s regional ambitions and Russia’s persistent influence. As Ukrainian scholar Yevgeniya Gaber observes, “The benefits of keeping the Russian fleet out of the region outweigh[ed] the benefits of sending NATO warships to the Black Sea.” NATO should consider the following broad principle.

Keep it regional (and low profile)

NATO should focus on strengthening the navies of its coastal members (Turkey, Romania and Bulgaria) and the alliance’s partners (Ukraine and Georgia) in the Black Sea. Maritime initiatives (such as joint naval patrols with coastal NATO countries, bolstering Romania’s and Bulgaria’s navies, enhancing intelligence sharing and investing in maritime infrastructure) could all strengthen regional security while respecting the Montreux Convention.

This would be more conducive to a stronger partnership with Ankara than bringing additional non-coastal NATO ships into the sea, which would not only alienate Turkey but also face Montreux restrictions. Indeed, bringing in non-regional ships without a safe harbour to withdraw to during moments of danger only increases their vulnerability. Ukraine’s newer strategies of using land-based missiles and drones against Russian warships have proven that the Black Sea is too narrow to be safe for surface ships. Submarines might still be useful, but the Montreux Convention only allows coastal states to bring submarines into the Black Sea.

In so doing, European NATO members need to be mindful of Turkey’s regional policies in the Black Sea and its strategy of co-opetition with Russia. This means the alliance should stick to low-profile, regional “mini-partnerships”—with coastal members. Turkey would respond more positively to these than high-profile cooperation with America, Britain or France. These mini-partnerships could, in turn, enhance the relationship between Turkey and NATO—but, thanks to the participation of Bulgaria and Romania, also the EU.

Turkey and the EU

Today’s Turkey is no longer the same partner that was eager to follow the US lead or push for EU membership two decades ago. It is a regional powerhouse determined to shape its destiny in international affairs, even as it veers towards illiberalism at home. Accepting this requires the EU to alter its approach.

Integrate defence

EU leaders should look to the Turkish defence industry for partnerships as member states ramp up their defences—and as Ukraine faces a war with “less America”.

The Turkish government is particularly keen to expand the role of its defence industry in meeting the EU’s new agenda for economic competitiveness and industrial production.

The EU and its member states should build on their existing cooperation with Turkish defence companies. Member states such as Poland and Italy could lead on this thanks to their existing ties with these companies.

Turkey’s defence manufacturing could complement Europe’s advanced technology to improve and increase European defence industrial output and enhance European security.

Put Black Sea stability first

Ukraine’s and the EU’s immediate security needs are pressing. But the EU should also identify other areas of mutual interest with Turkey and, where possible, foster “strategic interdependence”.

The Black Sea writ large could be one of these areas, providing an opening for the EU to establish a new and unique relationship with the Turkish government. This relationship could reverberate in other regions, such as the Caucasus, Central Asia and Syria, where Europe can benefit from Turkey’s reach and gain enhanced access to these regions.

After all, the coastline of Crimea and Ukraine is far from the only volatile area of the Black Sea. One opportunity for European-Turkish cooperation is the peace process between Armenia and Azerbaijan, where the two historic rivals have finalised, though not yet signed, a peace agreement. Despite an EU monitoring mission and recent European efforts to support Armenia’s resilience and democracy, the EU lacks sustainable, long-term leverage in the Caucasus. Turkey has close relations with Georgia and Azerbaijan and has been supportive of the peace talks, with a promise to open its land border with Armenia once there is a deal.

After a peace agreement, the EU and Turkey should collaborate to create a regional economic zone and a trade route linking Europe all the way to Central Asia (the Middle Corridor). This would bypass Anaklia Port in Georgia, which a Chinese company is building and will operate, reducing risks to European supply chains from Chinese manipulation.

In a post-Ukraine war scenario, European policymakers should work with their counterparts in Ankara to strengthen joint initiatives in the wider Black Sea. For example, they could work together to mitigate the effects of climate change in the region. They could also support efforts to connect together port cities—such as Odessa in Ukraine, Trabzon in Turkey and Varna in Bulgaria—to enhance their desirability as primary shipping and tourism destinations. Lastly, Turkey’s electrical and power grids (as well as undersea cables) could be used to support the EU’s integration into regional markets around the Black Sea.

European leaders could also encourage Turkey to revive some of its past initiatives for regional security, such as the Black Sea Naval Cooperation Task Group (BlackSeaFor)—though without including Russia initially—and Operation Black Sea Harmony, which would strengthen sub-regional security. Existing naval cooperation against sea mines between Turkey, Bulgaria and Romania could easily be extended to other friendly countries in the region and could cover other areas, too.

Broaden mutual interests

EU policymakers should also engage with Turkey outside of the Black Sea. Turkey is interested in greater cooperation on other issues, including the reconstruction of Syria, which is beyond the means of Turkey. The EU, with its experience in the rehabilitation of post-conflict societies and financial power, could easily partner with Turkey to help stabilise Syria, moderate the policies of its current rulers and enhance the quality of life for ordinary Syrians. European reconstruction funds and Turkey’s construction and energy sectors are equally significant for Syria’s economic recovery. The eventual repatriation of Syrian refugees to their homes is something both Turkey and European countries benefit from and can work together to achieve.

European leaders should also seek to enhance the EU’s position as Turkey’s top economic partner to bring Turkey closer to the EU. Successive Turkish governments have sought greater economic engagement with the EU and an upgrade to the customs union agreement. Although the European Commission agreed to this, political obstacles in Europe have blocked progress. Nonetheless, Turkey will still be seeking opportunities for engagement. It may also be willing to change its drumbeat of criticism of Europe to a warmer tone to improve its ties with European countries.

Be mindful of Turkish fears

Finally, EU leaders should be sensitive to Turkey’s public opinion. Turkey sees the Montreux Convention as one of the central pillars of Turkish sovereignty, so European messaging on the treaty should not challenge its existence. Moreover, European allies should reassure the Turkish public that it will not face Russia alone in the Black Sea if Turkish and European interests collide in another region. The country is just recovering from European defence sanctions, which for a time even hurt its navy as Germany stopped sending much-needed parts and ammunition.

Strategic realignment with Turkey

After a decade of tumult and estrangement, greater cooperation with Turkey will not be an easy reconfiguration for European policymakers. A reset with Turkey has not been a topic in the internal European conversation on the future of Europe, its security or even on Ukraine.

A pragmatic relationship between Turkey and Europe would, in fact, be a paradigm shift in Turkey-EU relations. It would open the possibility of integrating Turkey into Europe’s defence posture, which could bring immense geographic and military advantages for European security—albeit at the cost of accommodating Turkey’s caution and self-imposed restraints when it comes to dealing with Russia.

As the Ukraine war enters a critical and possibly final stage, NATO’s European allies need to think beyond the current military confrontation and identify areas in which Turkey can contribute to the future of European security. This could involve an enhanced physical presence in Black Sea security, defence industrial cooperation, and, in the more immediate term, greater Turkish-European coordination to pressure Russia towards a just and durable settlement in Ukraine.

Turkish leaders’ openness to regional cooperation with other coastal states in the Black Sea, like Romania and Bulgaria, and efforts to support the modernisation of Ukraine’s navy, through arms sales and shipbuilding, are essential elements of what Black Sea security could look like in a post-war environment. Many NATO allies and partners in the Black Sea region, including Bulgaria, Moldova and Romania, are vulnerable to Russian political or military meddling. They, and wider European security, would benefit from a stronger Turkish presence in the Black Sea.

For Europe, the Black Sea model offers a template of cooperation with Turkey—a NATO partner and an increasingly self-confident presence. It does not solve all of Europe’s problems with Turkey, but it could be a good start.

About the authors

Mustafa Aydın is professor of international relations at Kadir Has University (Istanbul), president of the International Relations Council of Turkey, and coordinator of the Global Academy. He is a regular commentator in media on global affairs and Turkish politics and has been leading the yearly “Turkey Trends” survey since 2010.

Aslı Aydıntaşbaş is a senior associate fellow at the European Council on Foreign Relations and a visiting fellow at the Brookings Institution in Washington, DC.  Her topics of focus include Turkish foreign policy and the external ramifications of its domestic politics.

Acknowledgments

We would like to thank the Wider Europe team at ECFR for their encouragement to tackle the Turkey question once again—but this time from the angle of European security. The publications team at ECFR has been very helpful in bringing the paper to the finishing line, and special thanks to Jeremy Cliffe and Kim Butson. Last, but not the least, a huge thanks to our editor, Kat Fytatzi, for her interest in the subject and for making it more readable.

[1] Private conversation with Turkish official in Washington DC, 2023.

[2] Private conversations with Turkish and former US officials in Washington and Istanbul, 2024.